For sure, but it doesn't really swing my overall assessment. From my point of view, the imaginary, generic % power of 2-PC wizard synergy is too difficult to gauge in the enormous fuzzy space of all possible class synergies. I am mildly familiar with descriptions of your gaming tables from previous threads. If I recall correctly, optimization features very prominently in your groups, and I think you're trying to suss out how powerful a combo this is. I don't think we'll ever get satisfactory data on that, but if you have a white room in mind, feel free to build it.
Not every tables cares about optimization that much, and I think that at least partially explains the infrequency of this combo in actual play. People be playin' what they wanna play. For people like myself, it's more a matter of not wanting to intrude on the game space another player chose to occupy, even if there are some great benefits to doing so. I would be more open to it if it arose during a collaborative, session-0 character creation phase.
Back to mechanics and power balance, I just feel like the overall benefits of having 2 wizards doesn't stand head and shoulders above other possibilities. neogod22 points out some of the great benefits of redundancy, and I do feel like a pair of wizards has better synergy than most other pairs of single classes. I'd be more nervous as a DM of a party with 2 wizards than a party with 2 rogues, that's for sure.
An aside, does this question arise from the thread http://www.enworld.org/forum/showthread.php?610300-What-is-the-best-quot-5th-quot-class/page3?
